Sputter Power Influenced Structural, Electrical, and Optical Behaviour of Nanocrystalline CuNiO₂ Films Formed by RF Magnetron Sputtering

Abstract

Copper nickel oxide (CuNiO2) films were deposited on glass and silicon substrates using RF magnetron sputtering of equimolar Cu50Ni50 alloy target at different sputter powers in the range of 3.1–6.1 W/cm2. The effect of sputter power on the chemical composition, crystallographic structure, chemical binding configuration, surface morphology, and electrical and optical properties of CuNiO2 films was investigated. The films formed at sputter power of 5.1 W/cm2 were of nearly stoichiometric CuNiO2. Fourier transform infrared spectroscopic studies indicated the presence of the characteristic vibrational bands of copper nickel oxide. The nanocrystalline CuNiO2 films were formed with the increase in grain size from 75 to 120 nm as the sputter power increased from 3.1 to 5.1 W/cm2. The stoichiometric CuNiO2 films formed at sputter power of 5.1 W/cm2 exhibited electrical resistivity of 27 Ωcm, Hall mobility of 21 cm2/Vsec, and optical bandgap of 1.93 eV.

One‐Step DcMS and HiPIMS Sputtered CIGS Films from a Quaternary Target

“…[ 42 ] According to Sreedhar et al, a rise in crystallinity causes a decrease in dislocation density and microstrain, which is consistent with our findings. [ 43 ] Another possibility is that the larger grains produced as a result of the increase in power will result in fewer grain boundaries in the growing film. [ 41 ]…”

Third-order non-linear optical switching and threshold limiting of NiO thin films

“…Transparent semiconducting material has extensive application on architectural windows, solar cells, heat reflectors, light transparent electrodes, thin-film photovoltaics, etc. Among various TCO materials, NiO is one of the promising candidates for making optoelectronic devices due to (i) p-type semiconductor with transparent conductivity 2 and (ii) the modulation of conductivity by phase deviation from stoichiometry and/or adding a doping element in the material 3,4 . Due to clear switching events, good reversibility, 3D staking compatibility, and simple structure, NiO can be used as a resistive random access memory device 5 .…”

Optical Properties of CuNiO2 Thin Films

“…Cu x Ni 1−x O thin films can be obtained by various methods: pyrolysis, sol-gel, electrodeposition, pulsed laser deposition, pulsed plasma deposition, thermal evaporation, DC magnetron sputtering, and RF magnetron sputtering [2,3]. Copper-nickel oxides in a thin film form are used as NO 2 gas sensor, anode for fuel cells, selective coating, solar cell, electrochromic devices, LEDs, photodiodes, ptype gate in heterojunction field-effect transistors, p-type transparent conductive coatings, antifungal coatings, and supercapacitor coatings [4][5][6].…”